Vibration damper



I Patented July 10, 1945 a UNITED STATE s] PA VIBRATION DAMPER p William F. Bankauf, East Paterson, N. J assign'or to Robins- Conveyors Incorporated, Passaic N. J., a corporation or New Jersey I I Application September 29, 194$,Serial No. 504,243 i lClaim. I (01. 188-1) This invention relates to a device for limiting the amplitude of vibration in a mechanical structure. It is illustrated and described as used in conjunction with a vibrating screen or the liken Looking at the drawing: Fig. 1 is an end elevation of the l to a screen structure; and

Fig. 2 is a section through 2-2 of Fig. 1.

Looking at the drawing, II represents the movable framework of a vibrating screen. This framework is mounted on suitable supports (not device attached I shown) which will permit oscillation of the framework with a limited amplitude of movement. Vibration of a screen of this kind may be had byIrotation of an off-center weight, such as that shown at 2, on pulley 3. Pulley 3 isrotatable on a shaft 4 which, in turn, is mounted on framework I. A belt 5 is designed to rotatepulley 3.

The vibration damper comprises a hollow cylindrical movable body shown at Ill. The outside of body I0 isequipped with bracket I I. A flange I2 secured to the vibratable frame ID or the screen is adaptedto be bolted tothe flange III by means of bolts I3. 'The result isthat thebody I II) of the vibration damper is securely fastened to the frame I of the vibrating screen and will move with it. I I 1 Inside the body III of the vibration damper are friction blocks I5 and I6 designed to pressagalnst stationary vertical plates I! and I8 under the urge of a coil spring I9 whichserves topush the blocks I5 and I6 outwardly against the inside face of the plates I1 and I8. The plates- I1 and IB are bolted or otherwiseIsecured to the fixed foundation 20 of the screen. Such bolts are shown at 2I and 22. I I In operation, the body I0, attached by means I of flange I2 to the vibrating frame I, vibrates with the frame I without engaging the blocks I5 and 3 I6. Thisxis because of clearance "at 0 between @the outside of blocks I5 and} I6 and the inside of body II]. I The amplitude of vibration of I 1 i the frame I is such that the body IIIIdoes'not engage the blocksIS and I6. If the amplitude of such vibration is increased as when the screen I passes through a critical vibration point in speed- 3 ing up or slowing down-the hollow cylindrical body In will'engage the blocks I5and t6 so as to move them on the plates I11 and I8. This movement is opposed by the friction between the blocks I5and I6 and the plates I1 andlfl, which friction is a function of the pressure exerted by the coil spring I 9.- I I I While I have shown the invention as embodied in a specific form, it is to be understood that I various changes in details may be made without departing from the scope of the invention as defined by the appended claim. I claim: I

I In a device of the character described, a body for attachment to a continuously vibrating memher having means for vibrating the member at a predetermined amplitude, means located in said body and spaced therefrom, means cooperating with said lastmeansto form a damping means engaging the body when the amplitude of vibra-,I

tion increases beyond the said predetermined I amplitude, said first means spaced a sufiicient distance so that the body only engages the damping means to limit the vibration when the vibration increases beyond the predetermined ampli-I .tude} as when the" vibrating member passes through a critical point; in speeding up or slowing down. I I IWILLIAM F. BANKAUF. 

